The setup looks like thisThat's a bit too little information to be able to help properly.
What are your water temperatures? Where are the water temperatures being read from? Where exactly is the clicking noise coming from? Could you make a video of it and upload it somewhere so we can take a look?
Are you cooling only the CPU with a chiller, or what does your full loop look like?
The CPU is just cooled with it and NO OC so standard setup.